import sys

from consts import *
from tokenizer import tokenize
from parser import build_tree


# RUNTIME

unary_operators = {
    "-": lambda a: -a,
    "+": lambda a: a
}

operators = {
    "+": lambda a, b: a + b,
    "-": lambda a, b: a - b,
    "*": lambda a, b: a * b,
    "^": lambda a, b: a ** b,
}

runtime = {
    "x": 10
}


def factorial(n):
    if n <= 1:
        return 1
    return n * factorial(n - 1)


runtime_functions = {
    "factorial": factorial
}

# END OF RUNTIME


def expr_eval(node):
    if node.type == NUMBER:
        return node.value
    elif node.type == SYMBOL:
        return runtime.get(node.value)
    elif node.type == FUNCALL:
        fun_name = node.value[0]
        args = list(map(expr_eval, node.value[1]))
        return runtime_functions.get(fun_name)(*args)
    elif node.type == OPERATOR:
        if node.subtype == UNARY:
            return unary_operators.get(node.left.subtype)(expr_eval(node.right))
        else:
            return operators.get(node.subtype)(expr_eval(node.left), expr_eval(node.right))


def main(*argv):
    if len(argv) != 0:
        data = argv[0]
    else:
        data = "2 + 3 * 4"
        # data = "(3 + 3 * 2) * -4"
        # data = "(2 + factorial(4, )) * 9"

    tokens = tokenize(data)
    node1 = build_tree(tokens)
    print(expr_eval(node1))


if __name__ == "__main__":
    main(*sys.argv[1:])